Neofungella claviformis Species

Synonymy

The stud-like zoarium grows from a spreading base, then contracts, forming a wide stalk, which spreads out again, with the upper surface convex.

The zooecia open both to the upper and to the lateral surfaces with round apertures, varying in size, and between these larger openings there are smaller round ones or cancelli, but there is no sign of any radial arrangement. On the walls between the zooecia there are minute elevations (8b). The internal pores of the zooecial tubes are usually in transverse lines and deeply sunk, giving the beaded appearance to the wall when broken (8a).

There is only one perfect specimen and one broken one, so that it has not been possible to make a complete examination, however a section cut shows the polypides in situ, though histolysis had commenced, but part of the cellular structure of the tentacles and other organs is distinguishable. In these sections, near the end of the zooecial tube, there is a membrane across it, which is what I have so often referred to as the « closure ». The parenchym extends up to this, and also on to its external surface, but above this closure the zooecial tube is filled with mud. The closure before preparation has of course been calcareous. The section being longitudinal the tentacles cannot be counted but there appear to be about twelve.

This in some particulars is like Domopora, and we know too little about Heteropora to judge how the group may ultimately be divided up. In Domopora stellata Goldf. from Shetland, a few of the terminal zooecia are closed by four or five calcareous rays, reminding us of the rays in Actinosoma (1). BUSK mentions rays in H. clavata Goldfuss, but these should not be confounded with the closures.

A specimen, from the Bancs des Aiguilles (S. Africa), Lat. 34° 57' S.- Long. 19° 55' E., 75 met., in the Museum d'histoire naturelle, Paris, has the zoarium exactly the same shape, but smaller, being under 5mm in diameter, whereas the Antarctic specimen is about 7mm, the zooecial walls are thinner giving a more angular shape to the openings, but lower down the zooecial tube contracts and becomes round. The zooecia on the side of the zoarium, that is on the upper part of the stalk of the zoarium, have a longitudinal direction and the zooecia are indicated externally by being slightly raised, but on the lower part of the zoarium this is not the case, as the surface is divided into irregular divisions closed by a punctured wall. In the more robust Antarctic specimen the zooecial tubes are only indicated for short distances, and openings are seen at intervals on all parts of the stalk. It seems right to consider the S. African and Antarctic as the same species, although the greater solidity of the second causes certain different appearances.

I have, in vain, made various efforts to obtain spirit specimens of Heteropora pelliculata Waters, or other Heteropora from which I could cut sections, as a better knowledge of the anatomy is much to be desired, but although we have not yet learnt anything about the ovicells and some other organs, there have been no grounds for doubting that the recent Heteropora were Cyclostomatous Bryozoa. The pores between the tubes, the closures, the rays, the cancelli are all so similar to what are constantly found in Lichenopora that we have here the nearest relationship of any well studied family. ORTMANN (I) who found H. pelliculata Waters in the Japan Seas, says he has been doubtful as to Heteropora being Bryozoa, since Dr DODERLEIN pointed out to him that the thin covering membrane consisted of three-rayed sponge spicules. I think it is hardly necessary to say that the membrane over the Japan specimens which I described was nothing of the kind.

GREGORY (Catalogue of the Cretaceous Bryozoa, vol. I, p. 404) thinks, that the living species referred to Heteropora, probably belong to his suborder Dactylethrata. Until we know more about the anatomy it will be impossible to be sure about the position, but without entering into the validity of the suborders of GREGORY, I must emphatically state, that supported by sections I have prepared of Jurassic, Cretaceous, and Tertiary fossils, there is no doubt of there being in all these formations, fossils closely related to the recent Heteropora, and probably of the same genus. That there are many fossils similar in form to Heteropora, which will have to be separated, is of course probable.

Many paleontologists have undoubtedly attached too much importance to the spaces between the zooecial tubes, for, while they must always be a valuable specific character, undue weight should not be given to them, as there is at present no reason for considering, that they contained special organs.